1. Field of the Invention
This invention relates to a solid-state image sensing device which can be applied, for example, to an amplification-type CMOS image sensor used in a mobile telephone with an image sensor, digital camera, video camera or the like.
2. Description of the Related Art
Conventionally, methods for widening the dynamic range of a CMOS image sensor are proposed in Jpn. Pat. Appln. KOKAI Publication No. 2001-189893 and Jpn. Pat. Appln. KOKAI Publication No. 2000-23044, for example. The former method is applied to incomplete transfer type photodiodes, but in this case, there is a possibility that residual images and white defects will occur and it is difficult to enhance the image quality. On the other hand, since the latter method corresponds to complete transfer type photodiodes, there is no possibility that residual images and white defects occur unlike the former method. However, since the dynamic range is widened by use of a detecting section, unevenness of dark-time and KTC noises due to a leak current in the detecting section are generated and there occurs a possibility that the image quality will be degraded due to a factor different from that of the former method. In addition, since signals of long exposure time and short exposure time are added and output in each of the above methods, it is difficult to separate the signals of long exposure time and short exposure time from each other.